Integrated circuits often include a plurality of pins that are used to make electrical connections to components beyond the integrated circuit, such as a power pin for supplying power, a ground pin for grounding purposes, and a signal pin. Exemplary signal pins include an input signal pin for supplying an external signal to the integrated circuit and an output signal pin for outputting a signal from the integrated circuit. Typically, a gate grounded transistor is electrically connected between different pins for electrostatic discharge protection, so an integrated circuit with three pins would have at least three gate grounded transistors electrically connected between the pins. These gate grounded transistors discharge excess voltage that may arise due to an electrostatic discharge or other types of electrical noise.
The gate grounded transistor has a holding voltage that is an inherent feature of the transistor, where the “holding voltage” is the minimum voltage that must be applied for an electronic device to remain in the “on” state. Many typical gate grounded transistors have a holding voltage of about 6 volts, but other designs may have other holding voltages. The holding voltage should be at or above the operating voltage for the integrated circuit to prevent undesirable trips of the gate grounded transistor. For example, if the operating voltage of an integrated circuit was 6 volts, minor voltage variations over time (i.e. “noise”) could frequently trip the gate grounded transistor with a holding voltage of 6 volts because there is essentially no safety margin between the holding voltage and the operating voltage. Furthermore, the designed operating voltage may be limited by the holding voltage of gate grounded transistors used for electrostatic discharge protection.
Accordingly, it is desirable to provide integrated circuits with transistors that have higher holding voltages than traditional transistors, where these transistors may be used for electrostatic discharge protection, and methods of producing the same. In addition, it is desirable to develop transistors for electrostatic discharge protection that do not increase the manufacturing processes needed to produce an integrated circuit. Furthermore, other desirable features and characteristics of the present embodiment will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.